Non-aqueous sol-gel synthesis of ultra small persistent luminescence nanoparticles for near-infrared in vivo imaging

Abstract

Abstract Ultra-small ZnGa 2 O 4 :Cr 3+ nanoparticles (6a nm) that exhibit near-infrared (NIR) persistent luminescence properties are synthesized by using a non-aqueous sol-gel method assisted by microwave irradiation. The nanoparticles are pegylated, leading to highly stable dispersions under physiological conditions. Preliminary in vivo studies show the high potential for these ultra-small ZnGa 2 O 4 :Cr 3+ nanoparticles to be used as in vivo optical nanotools as they emit without the need for in situ excitation and, thus, avoid the autofluorescence of tissues. Luminescing with persistence: Ultra-small ZnGa 2 O 4 :Cr 3+ nanoparticles (6a nm) that exhibit near-infrared persistent luminescence are synthesized by using a non-aqueous sol-gel method. The nanoparticles are shown to be useful optical nanotools as they emit without the need for continuous in situ excitation and they avoid tissue autofluorescence.